Registrant name changes for a .uk domain name (.co.uk/.me.uk/.org.uk/.uk) can only be performed via the .UK registry, Nominet.
The domain owner must access their Nominet account online to make these changes. The login portal is available at secure.nominet.org.uk, and credentials are typically provided during initial domain registration.
Cost: Nominet charges a fee of £10 plus VAT for ownership modifications.